The present invention relates generally to a method of and apparatus for displaying photographic information in a viewfinder of a photographic apparatus. More particularly, it relates to a method of and apparatus for displaying, in a viewfinder, alphanumeric range information together with exposure information utilizing such range information.
It is known generally that viewfinders are used for purposes of displaying various forms of information essential for enhancing the operation of a camera. For example, viewfinder windows are used to display exposure data. Earlier approaches along these lines utilized a needle and a scale of a meter which would appear superimposed on the scene. Some cameras with automatic exposure control systems incorporate a visible color signal in the viewfinder for warning the user when the prevailing ambient light is inadequate for a correct exposure. Other automatic cameras display the aperture value and shutter speed selected by the automatic exposure mechanism so that the photographer has a running check of the scene lighting conditions. U.S. Pat. No. 4,322,153 is an example of such a system. Still other kinds of cameras employ means for visually indicating the range of a subject to be photographed. For example, some single lens reflex cameras employ optical systems which provide an image in the viewfinder of the range value on the distance adjusting ring located on the camera. U.S. Pat. Nos. 3,174,416 and 4,053,912 are examples of such display systems. Still other kinds of cameras display ranging information with graphic symbols representing different ranging zones, such as described in U.S. Pat. No. 4,530,583. Known viewfinders may show in other ways the focusing zone to which the lens has been set.
None of the known viewfinder display systems, however, disclose a system in which subject range is automatically and electronically displayed in the viewfinder in alphanumeric form. Furthermore, none of the known prior art discloses such display system in which the displayed alphanumeric range information is coupled with exposure information utilizing such range information.